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 ###Instrução: Em qual superfície Mathieu jogou contra Antonio Veić?
 ###Tabelas: CREATE TABLE classification_leadership_progress_table (classification_leadership_progress_table_id AUTO_INCREMENT PRIMARY KEY, Stage INT, Winner VARCHAR, General classification VARCHAR, Mountains classification VARCHAR, Points classification VARCHAR, Youth classification VARCHAR, Team Classification VARCHAR) CREATE TABLE epic-m_and_epic-x (epic-m_and_epic-x_id AUTO_INCREMENT PRIMARY KEY, Frame size VARCHAR, Width INT, Height INT, Mpix INT, Aspect Ratio VARCHAR, max. fps INT, max. fps HDRx INT, lowest possible REDCODE at 24 fps VARCHAR, lowest possible REDCODE at max. fps VARCHAR) CREATE TABLE human_resource_development (human_resource_development_id AUTO_INCREMENT PRIMARY KEY, Region VARCHAR, Physician (GP & specialist) INT, Physician : Population Ratio VARCHAR, Health Officer INT, HO : Population Ratio VARCHAR, All Nurses INT, Nurse : Population Ratio VARCHAR, Mid-wives VARCHAR, Mid Wife: Population Ratio VARCHAR, HEW* VARCHAR) CREATE TABLE singles (singles_id AUTO_INCREMENT PRIMARY KEY, Date VARCHAR, Tournament VARCHAR, Surface VARCHAR, Opponent in the Final VARCHAR, Score in the Final VARCHAR) CREATE TABLE singles_18–8 (singles_18–8_id AUTO_INCREMENT PRIMARY KEY, Edition VARCHAR, Round VARCHAR, Date VARCHAR, Surface VARCHAR, Opponent VARCHAR, Result VARCHAR)  
SELECT Surface FROM singles WHERE Opponent in the Final = antonio veić